The invention is based on a wiper blade. In a known wiper blade of this type (DE 2 853 487 A1), the facing longitudinal edges of the springs lie against the base of the respective longitudinal groovexe2x80x94i.e., on the bridgexe2x80x94and are held in this position by way of claws of rack parts of the wiper blade that encompass the outer edges of the springs. As a result of this measure, a certain stiffening of the bridge is achieved, which can impair the fit of the wiper blade to the window curvature. Moreover, due to the stiffening of the bridge mentioned previously, the wiper strip tips out of its working dragging position into its other working dragging position while the working direction of the wiper blade changes, causing an undesired loud noise.
In the wiper blade according to the invention the springs can also move in their longitudinal grooves transversely to their longitudinal span if the bridge deforms when stressed accordingly. This prevents stiffening of the bridge and improves the fit of the wiper strip to the window curvature, and a quieter wiper operation is achieved as a result of the coupling of noise achieved in this manner.
In a wiper blade in which at least one section of each of the two springs projects out of its longitudinal groove, whereby these sections are opposite to each other as compared with the longitudinal center line of the wiper strip, and, on at least one of these pair of sections, a component that overlaps the two springs in the manner of a bridge lies against the opposite longitudinal edges, a simple wiper blade assembly is achieved if at least one means of maintaining the clearance is situated on the component.
A practical design of the invention provides that the two end sections of the two springs project out of their grooves in the longitudinal direction and transversely to the longitudinal direction of the wiper strip, that one end cap each serving as a bridge-like component is situated on these end sections, and that means of maintaining the clearance that cooperate with the facing longitudinal edges of the springs and hold both ends of the springs in the specified position are situated on the end cap.
To secure the springs in their longitudinal grooves, the end cap has a base plate situated on the side of the springs opposite to the wiper lip which includes L-shaped projections that extend in the longitudinal direction of the springs, one L-leg each of which is connected with the base plate, and other L-legs each of which are opposite to each other, and that means of maintaining the clearance that extend between the facing longitudinal edges of the springs and that are adjacent to these are situated on the base plate. This produces a space for the springs between the one L-leg and the means of maintaining the clearance limited by the bridge in which the springs can slide in the longitudinal direction and transversely to their longitudinal span, however.
A particularly simple solution for the arrangement of the means of maintaining the clearance is produced when it is formed by a peg held on the base plate.
If the end cap is made out of a spring-elastic material and the peg is situated on a tongue of the end cap that can be moved against a retractive force out of its operating position into an assembly position, this results in simple installation and removal of the wiper blade.
According to another embodiment of the invention, the end cap includes a wall opposite to the longitudinal end edges of the springs on which the means of maintaining the clearance are situated in the longitudinal direction of the springs and extend between them. This design of the invention makes it possible to automatically install end caps that can be slid onto the springs in the longitudinal direction, because, when these end caps are installed, the means of maintaining the clearance also reach their specified position at the same time.
If these end caps are made of a spring-elastic material, and the means of maintaining the clearance are formed out of two finger-like projections of the wall that can be moved against spring force, which projections lie under tension against one of the two facing longitudinal edges of the springs in the operating position of the end cap, the manufacturing tolerancesxe2x80x94which cannot be avoided with reasonable effortxe2x80x94are offset at the same time.
According to another embodiment of the invention, the bridge-like component is designed as a connecting device for a wiper arm in the middle section of the wiper blade on the side of the springs opposite to the wiper lip, which includes projections that encompass the outer longitudinal edges of the springs in claw-like fashion, whereby the means of maintaining the clearance is formed by means situated on the connecting device that grip in at least one recess of the respective springs. Although this design may be usable in and of itself, it can also be used with advantage with the embodiments of the inventionxe2x80x94use of the end caps designed accordinglyxe2x80x94mentioned previously.
With this other embodiment, it is appropriate that the means of maintaining the clearance is formed by separate components held on the connecting device that penetrate the springs in recesses provided there.
To secure the end caps on the end sections of the springs, a shoulder that points toward its other end section is situated on each end section of each spring on their opposite ends, to which a counter-shoulder of the end cap is assigned that cooperates with this. When the wiper blade is installed, the shoulder and counter-shoulder cooperate in such a way that the end caps are held captive on the wiper blade. Since the positioning of the means of maintaining the clearance is achieved after the specified position of the end caps is reached, no problems are encountered when installing the end caps.